-
List major characteristics used to classify and identify the following bacteria and list two examples for the 5 groups of Proteobacteria
- Proteobacteria (general): most gram-negative chemoheteroprophic bacteria. Largest taxonomic group.
- Alphaproteobacteria: Capable of growth at very low levels of nutrients. N2 fixation in plants, plant and human pathogens.
- Bartonella (human pathogens, can survive phagocytosis)
- Rhizobium (infects roots of legumes and forms nodules for N2 fixation)
- Betaproteobacteria: Often use H2, NH3, and CH4 as nutrient substances. Several important pathogenic bacteria.
- Thiobacillus (important in sulfur cycle, H2S->SO42-)
- Zoogloea (slimy masses in aerobic sewage-treatment processes, essential)
- Gammaproteobacteria: largest subgroup, great variety.
- Pseudomonas (aerobic, gram negative, rods, motile by polar flagella, produces water soluble pigments, use nitrate as final electron acceptor, metabolically diverse)
- Enterobacteriales (live in intestines, peritrichous flagella, facultative anaerobes, have fimbrae for attachment)
- Deltaproteobacteria: includes bacteria that are predators of other bacteria, and bacteria that are important contributers to the Sulfur cycle
- Bdellovibrio (preys on other bacteria, reproduces in and lyses host cell to release new cells)
- Desulfovibrio (Sulfur-reducing bacteria, use S instead of O2 as final e- acceptor producing H2S)
- Epsilonproteobacteria: slender gram negative rods that are helical or curved, both important genera are motile via flagella and microaerophilic
- Campylobacter (single polar flagellum, C. jejuni is the leading cause of gastroenteritis)
- Helicobacter (multiple flagella, has urease, causes peptic ulcers and stomach cancers)
-
List major characteristics used to classify and identify the following bacteria and list two examples for two types of non-proteobacteria (gram negative)
- Several physiologically and morphologically distinctive photosynthesizing bacteria. Cyanobacteria produce oxygen during photosynthesis, and the green sulfur and green nonsulfur bacteria do not produce oxygen
- Cyanobacteria: oxygenic photosynthesis. Fix nitrogen with specialized cells (heterocysts). Gliding motility. Purple and green sulfur bacteria, living in deep freshwater do not produce O2
- Chlamydiae: intracellular pathogens that do not have peptidoglycan, STI/urethritis
-
List major characteristics used to classify and identify the following bacteria and list two examples for non-proteobacteria (Gram positive)
- Divided into 2 phyla, Firmicutes (low G+C ratios) and Actinobacteria (high G+C ratios). Mycoplasmas are grouped with Firmicutes even though they do not have a cell wall.
- Firmicutes: important endospore forming bacteria (Clostridium, Bacillus), mycoplasma, Staphylococcus, Enterococcus, and Streptococcus
- Clostridium (endospore-producing rods. Obligate anaerobes. Causes disease by production of neurotoxins)
- Lactobacillus (lactic-acid producing, commercially used in production of saurkraut/pickles/yogurt, found on human body as normal flora)
- Actinobacteria: highly pleomorphic, several important pathogenic genera (Mycobacterium), actinomycetes (star shape, resemble filamentous fungi),
- Mycobacterium (Aerobic, non-endospore forming rods. Mycolic acid in cell walls - acid fast stain, slow growth, pathogens for lepracy and tuberculosis)
- Nocardia (Aerobic, soil bacterium, causes pulmonary infection, acid fast)
-
List major characteristics used to classify and identify the following bacteria and list two examples for each Chlamydiae, Spirochaetes, Bacteriodetes
- Chlamydiae: Do not contain peptidoglycan in their cell walls. Gram negative. Cocci. Do not require insects/ticks for transmission. Pathogenic. (eg Chlamydia and Chlamydophila)
- Spirochaetes: Coiled morphology (metal spring), motility by endoflagella causing corkscrew rotation, found in human oral cavity (Treponema [syphillis], Borrelia [relapsing fever, lime disease])
- Bacteriodetes: Anaerobic bacteria. Gram negative. Nonendospore forming. (Bacteriodes [GI tract, can cause infections during surgery, nonmotile], Cytophaga [important in cellulose/chitin degredation -soil- Gliding motility]
-
Define the Domain Archaea, list characteristics that make them unique and list examples
- Prokaryotes whose cell walls lack peptidoglycan (pseudomurein)
- Highly diverse: morphology, reproduction, physiology, nutrition, extremophiles
- Sulfolobus: hyperthermophile found in hyperthermal vents
- Methanobacterium: methanogen used for sewage treatment
- Halobacterium: halophile found in the great salt lakes. Lyses under low salt concentration
-
Identify medically important bacteria
- Wolbachia: most common infectious bacterial genus. Live inside cells of hosts, typically insects, difficult to culture.
- Burkholderia: able to degrade 100+ sources, can actually grow in disinfectant in hospitals
- Bordetella: perussis (whooping cough)
- Neisseria: gonorrhoea
- Pseudomonas: opportunistic infection, can grow from many C sources (or N, protein, lipid) and with very little
- Enterics: inhabit the GI tract, fimbrae help adhere to surfaces, sex pili often transmit antibiotic resistance, lyse other bacteria
- Escherichia: GI tract inhabitant, can be cause ot UTI, diarrhea, foodborne illnes
- Salmonella: GI tract inhabitant, typhoid fever is most sever illness
- Shigella: bacillary dysentary, only found in humans
- Yersinia: cause of the plague, transmitted from rats to humans via flea
- Campylobacter: leading cause of foodborne intestinal disease
- Helicobacter: most common cause of peptic ulcers, can cause stomach cancer
- Staphylococcus: infection of surgical wounds, quick antibiotic resistance development, produces toxins
- Streptococcus: causes greater variety of diseases than any other group. Beta hemolytic vs. non-beta hemolytic.
- Enterococcus: leading cause of nosocomial infections
- Listeria: capable of growth at regigeration temperature
- Clostridium: due to endospore's resistance
- Mycobacterium: tuberculosis, lepracy
-
Indicate which bacteria area: not readily gram stained, intracellular parasites, lack cell walls, acid fast
- Not readily gram stained: Mycoplasmatales, Mycobacterium, Nocardia,
- Intracellular parasites: Rickettsia, Brucella, Wolbachia, Coxiella, Chlamydia
- Lack cell walls: Mycoplasmatales
- Acid fast: Mycobacterium, Nocardia,
|
|
